| 摘要 |
During mask inspection predominantly defects of interest which also occur during wafer exposure. Therefore, the aerial images generated in the resist and on the detector have to be as far as possible identical. In order to achieve an equivalent image generation, during mask inspection the illumination and, on the object side, the numerical aperture are adapted to the scanner used. A further form of mask inspection microscopes serves for measuring the reticles and is also referred to as a registration tool. The illumination is used by the stated conventional and abaxial illumination settings for optimizing the contrast. The accuracy of the registration measurement is thus increased. The invention relates to a mask inspection microscope for variably setting the illumination. It serves for generating an image of the structure (150) of a reticle (145) arranged in an object plane in a field plane of the mask inspection microscope. It comprises a light source (5) that emits projection light, at least one illumination beam path (3, 87, 88), and a first diaphragm for generating a resultant intensity distribution of the projection light in a pupil plane (135) of the illumination beam path (3, 87, 88), that is optically conjugate with respect to the object plane. According to the invention, the mask inspection microscope has at least one further diaphragm for generating the resultant intensity distribution. The first diaphragm and the at least one further diaphragm influence the resultant intensity distribution of the projection light at least partly at different locations of the pupil plane (135).
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